Look at all the pro gamers; they aren't bringing their mouse every where they go, they just save their settings rock in another mouse and are ready for gaming.
Maybe that's the market they're trying to target.
Do those still exist? I remember playing StarCraft a lot with friends in such a place, but this was like... 8 years ago?
Even still, there are niches to fill in such places. Relatively recently (last year I think) a place here opened with exceptionally high performance PCs/net connection, comfortable chairs, etc, which focuses on gaming. Every time I walk past it's packed, so they're doing something right.